It is unclear from your description exactly which hyperlinks no longer work.
Under Tools, run the design checker to see if that tells you what you did to
the design to create the problems. If you overlap some design elements with
text boxes with hyperlinks, that can kill hyperlinks, as one example.
Consider what you did when you edited the file, that broke the hyperlink,
and perhaps that will lead to the solution of how to fix it.

It also sounds like you may have broken the wizard built navbar when you
added the page. You might be able to repair it. Go to that page in your Pub
file, tools, web page options. Uncheck the option to "add hyperlink to new
navigation bars...", and the navbar should update itself and pull the page
from the navbar. Then do the reverse, check the option and the navbar should
update and add in that page.

You can also select the navbar, click the little wand that appears below,
and then to the left of your page > Change Navigation bar, click Add,
Remove, and reorder links. That will bring up a Navigation Bar Properties
dialog where you can Add, Remove, move or modify links....

And, go to Help and type in "navigation" and read the material provided, and
that might give you some insight into what is going wrong.

And if none of that helps, post the URL of your website, and specify exactly
which links are not working.

DavidF